Marigold Carnival is clear glass that has been sprayed (whilst very hot) with a liquid solution of various metallic salts – this is what produces the iridescent effect. Different chemical solutions produced different iridescent effects – the orange of marigold was produced by iron salts (ferric chloride). The temperature of the glass, when it was sprayed, had an effect on the “look” of the iridescence too.
Carnival Glass colours are usually categorised according to the base colour of the glass, but marigold is an exception. The name comes from the iridescence itself – that very characteristic orange colour. There are several variations, from pastel to pumpkin.
In the case of your powder bowl, it looks as if the iridescence has been applied to the interior of the bowl only, thus giving a slightly frosty look to the outside of the glass. But it is still marigold.
This isn’t unusual with Carnival. Some makers liked to “play” a little with their application of iridescence. Dugan, for example, sometimes put iridescence only on the interior of a piece, and not on the exterior.
If you’d like to take a look at an article we wrote on Carnival colours, it might help a little. Colour – and Carnival – is a very complex subject.
http://www.thistlewoods.net/Carnival-colours.htmlHope this helps a bit.
Glen